Sometimes being and working fairly will bring you more money than trying to cheat, rob and steal. While facing a giant like Google you should not be using deceptive methods as you may be penalized hardly and get your account suspended. So we will be exploring together some issues and concerns (i.e where are Google ads prohibited to use?) while dealing with Google Adsense Program.

Remember!. You must be aware that clicking your own ads displayed on your website is prohibited and could cause your account to be suspended. So is, using automated systems to generate false clicks and impressions.
This means that showing your website to Paid To Click, Traffic Exchanges, Autosurf and similar Programs is not allowed by Google.

Remember!.Also you as a Publisher must not push visitors to click ads on your website by putting phrases like: "help our company by clicking ads", or similar behavior. But you are allowed to write above Google ad units only:"Sponsored Links".

Remember!.Your site must not have content which is illegal, promotes illegal content, and breaks other reserved rights. Prohibition of displaying ads is also to websites, their primary language is not supported by Google. Main topics where placing ads is not allowed are: gambling, drugs, sexual content, alcohol and cigarettes promoting, hacking..etc. So avoid placing Google ads if your website has similar content.

Remember!.Google ads must not be included in pop-ups, pop-unders and inside mass emails through third part websites.
You must not try to modify Google ads code, but just paste it into your website. Placing Referral products must not be associated with email requesting...etc.

Remember!.You are allowed to put: 3 ad units, 3 link units, 3 referral products and 2 search boxes within a single page, all together. You must not put ad units on pages with no content and be sure that ads are visibly clear.

These are some of the most import issues that you must deal with while putting Adsense codes into your websites, and I do not carry any responsibility for user misunderstandings. For further and detailed information about this topic check from time to time Google Adsense Program Policies.